Journal or Book Title
After substantial progress over the last 15 years, the “algebraic CSP-dichotomy conjec- ture” reduces to the following: every local constraint satisfaction problem (CSP) associ- ated with a finite idempotent algebra is tractable if and only if the algebra has a Taylor term operation. Despite the tremendous achievements in this area, there remain exam- ples of small algebras with just a single binary operation whose CSP resists classification as either tractable or NP-complete using known methods. In this paper we present some new methods for approaching this problem, with particular focus on those techniques that help us attack the class of finite algebras known as “commutative idempotent bi- nars” (CIBs). We demonstrate the utility of these methods by using them to prove that every CIB of cardinality at most 4 yields a tractable CSP.
Bergman, Clifford and Demeo, William, "Universal Algebraic Methods for Constraint Satisfaction Problems" (2017). Mathematics Publications. 191.